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diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h
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+++ b/arch/powerpc/include/asm/book3s/32/pgtable.h
@@ -0,0 +1,627 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_POWERPC_BOOK3S_32_PGTABLE_H
+#define _ASM_POWERPC_BOOK3S_32_PGTABLE_H
+
+#include <asm-generic/pgtable-nopmd.h>
+
+/*
+ * The "classic" 32-bit implementation of the PowerPC MMU uses a hash
+ * table containing PTEs, together with a set of 16 segment registers,
+ * to define the virtual to physical address mapping.
+ *
+ * We use the hash table as an extended TLB, i.e. a cache of currently
+ * active mappings. We maintain a two-level page table tree, much
+ * like that used by the i386, for the sake of the Linux memory
+ * management code. Low-level assembler code in hash_low_32.S
+ * (procedure hash_page) is responsible for extracting ptes from the
+ * tree and putting them into the hash table when necessary, and
+ * updating the accessed and modified bits in the page table tree.
+ */
+
+#define _PAGE_PRESENT 0x001 /* software: pte contains a translation */
+#define _PAGE_HASHPTE 0x002 /* hash_page has made an HPTE for this pte */
+#define _PAGE_USER 0x004 /* usermode access allowed */
+#define _PAGE_GUARDED 0x008 /* G: prohibit speculative access */
+#define _PAGE_COHERENT 0x010 /* M: enforce memory coherence (SMP systems) */
+#define _PAGE_NO_CACHE 0x020 /* I: cache inhibit */
+#define _PAGE_WRITETHRU 0x040 /* W: cache write-through */
+#define _PAGE_DIRTY 0x080 /* C: page changed */
+#define _PAGE_ACCESSED 0x100 /* R: page referenced */
+#define _PAGE_EXEC 0x200 /* software: exec allowed */
+#define _PAGE_RW 0x400 /* software: user write access allowed */
+#define _PAGE_SPECIAL 0x800 /* software: Special page */
+
+#ifdef CONFIG_PTE_64BIT
+/* We never clear the high word of the pte */
+#define _PTE_NONE_MASK (0xffffffff00000000ULL | _PAGE_HASHPTE)
+#else
+#define _PTE_NONE_MASK _PAGE_HASHPTE
+#endif
+
+#define _PMD_PRESENT 0
+#define _PMD_PRESENT_MASK (PAGE_MASK)
+#define _PMD_BAD (~PAGE_MASK)
+
+/* We borrow the _PAGE_USER bit to store the exclusive marker in swap PTEs. */
+#define _PAGE_SWP_EXCLUSIVE _PAGE_USER
+
+/* And here we include common definitions */
+
+#define _PAGE_KERNEL_RO 0
+#define _PAGE_KERNEL_ROX (_PAGE_EXEC)
+#define _PAGE_KERNEL_RW (_PAGE_DIRTY | _PAGE_RW)
+#define _PAGE_KERNEL_RWX (_PAGE_DIRTY | _PAGE_RW | _PAGE_EXEC)
+
+#define _PAGE_HPTEFLAGS _PAGE_HASHPTE
+
+#ifndef __ASSEMBLY__
+
+static inline bool pte_user(pte_t pte)
+{
+ return pte_val(pte) & _PAGE_USER;
+}
+#endif /* __ASSEMBLY__ */
+
+/*
+ * Location of the PFN in the PTE. Most 32-bit platforms use the same
+ * as _PAGE_SHIFT here (ie, naturally aligned).
+ * Platform who don't just pre-define the value so we don't override it here.
+ */
+#define PTE_RPN_SHIFT (PAGE_SHIFT)
+
+/*
+ * The mask covered by the RPN must be a ULL on 32-bit platforms with
+ * 64-bit PTEs.
+ */
+#ifdef CONFIG_PTE_64BIT
+#define PTE_RPN_MASK (~((1ULL << PTE_RPN_SHIFT) - 1))
+#define MAX_POSSIBLE_PHYSMEM_BITS 36
+#else
+#define PTE_RPN_MASK (~((1UL << PTE_RPN_SHIFT) - 1))
+#define MAX_POSSIBLE_PHYSMEM_BITS 32
+#endif
+
+/*
+ * _PAGE_CHG_MASK masks of bits that are to be preserved across
+ * pgprot changes.
+ */
+#define _PAGE_CHG_MASK (PTE_RPN_MASK | _PAGE_HASHPTE | _PAGE_DIRTY | \
+ _PAGE_ACCESSED | _PAGE_SPECIAL)
+
+/*
+ * We define 2 sets of base prot bits, one for basic pages (ie,
+ * cacheable kernel and user pages) and one for non cacheable
+ * pages. We always set _PAGE_COHERENT when SMP is enabled or
+ * the processor might need it for DMA coherency.
+ */
+#define _PAGE_BASE_NC (_PAGE_PRESENT | _PAGE_ACCESSED)
+#define _PAGE_BASE (_PAGE_BASE_NC | _PAGE_COHERENT)
+
+/*
+ * Permission masks used to generate the __P and __S table.
+ *
+ * Note:__pgprot is defined in arch/powerpc/include/asm/page.h
+ *
+ * Write permissions imply read permissions for now.
+ */
+#define PAGE_NONE __pgprot(_PAGE_BASE)
+#define PAGE_SHARED __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW)
+#define PAGE_SHARED_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | _PAGE_EXEC)
+#define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER)
+#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
+#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER)
+#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
+
+/* Permission masks used for kernel mappings */
+#define PAGE_KERNEL __pgprot(_PAGE_BASE | _PAGE_KERNEL_RW)
+#define PAGE_KERNEL_NC __pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | _PAGE_NO_CACHE)
+#define PAGE_KERNEL_NCG __pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | _PAGE_NO_CACHE | _PAGE_GUARDED)
+#define PAGE_KERNEL_X __pgprot(_PAGE_BASE | _PAGE_KERNEL_RWX)
+#define PAGE_KERNEL_RO __pgprot(_PAGE_BASE | _PAGE_KERNEL_RO)
+#define PAGE_KERNEL_ROX __pgprot(_PAGE_BASE | _PAGE_KERNEL_ROX)
+
+#define PTE_INDEX_SIZE PTE_SHIFT
+#define PMD_INDEX_SIZE 0
+#define PUD_INDEX_SIZE 0
+#define PGD_INDEX_SIZE (32 - PGDIR_SHIFT)
+
+#define PMD_CACHE_INDEX PMD_INDEX_SIZE
+#define PUD_CACHE_INDEX PUD_INDEX_SIZE
+
+#ifndef __ASSEMBLY__
+#define PTE_TABLE_SIZE (sizeof(pte_t) << PTE_INDEX_SIZE)
+#define PMD_TABLE_SIZE 0
+#define PUD_TABLE_SIZE 0
+#define PGD_TABLE_SIZE (sizeof(pgd_t) << PGD_INDEX_SIZE)
+
+/* Bits to mask out from a PMD to get to the PTE page */
+#define PMD_MASKED_BITS (PTE_TABLE_SIZE - 1)
+#endif /* __ASSEMBLY__ */
+
+#define PTRS_PER_PTE (1 << PTE_INDEX_SIZE)
+#define PTRS_PER_PGD (1 << PGD_INDEX_SIZE)
+
+/*
+ * The normal case is that PTEs are 32-bits and we have a 1-page
+ * 1024-entry pgdir pointing to 1-page 1024-entry PTE pages. -- paulus
+ *
+ * For any >32-bit physical address platform, we can use the following
+ * two level page table layout where the pgdir is 8KB and the MS 13 bits
+ * are an index to the second level table. The combined pgdir/pmd first
+ * level has 2048 entries and the second level has 512 64-bit PTE entries.
+ * -Matt
+ */
+/* PGDIR_SHIFT determines what a top-level page table entry can map */
+#define PGDIR_SHIFT (PAGE_SHIFT + PTE_INDEX_SIZE)
+#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
+#define PGDIR_MASK (~(PGDIR_SIZE-1))
+
+#define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE)
+
+#ifndef __ASSEMBLY__
+
+int map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot);
+void unmap_kernel_page(unsigned long va);
+
+#endif /* !__ASSEMBLY__ */
+
+/*
+ * This is the bottom of the PKMAP area with HIGHMEM or an arbitrary
+ * value (for now) on others, from where we can start layout kernel
+ * virtual space that goes below PKMAP and FIXMAP
+ */
+#include <asm/fixmap.h>
+
+/*
+ * ioremap_bot starts at that address. Early ioremaps move down from there,
+ * until mem_init() at which point this becomes the top of the vmalloc
+ * and ioremap space
+ */
+#ifdef CONFIG_HIGHMEM
+#define IOREMAP_TOP PKMAP_BASE
+#else
+#define IOREMAP_TOP FIXADDR_START
+#endif
+
+/* PPC32 shares vmalloc area with ioremap */
+#define IOREMAP_START VMALLOC_START
+#define IOREMAP_END VMALLOC_END
+
+/*
+ * Just any arbitrary offset to the start of the vmalloc VM area: the
+ * current 16MB value just means that there will be a 64MB "hole" after the
+ * physical memory until the kernel virtual memory starts. That means that
+ * any out-of-bounds memory accesses will hopefully be caught.
+ * The vmalloc() routines leaves a hole of 4kB between each vmalloced
+ * area for the same reason. ;)
+ *
+ * We no longer map larger than phys RAM with the BATs so we don't have
+ * to worry about the VMALLOC_OFFSET causing problems. We do have to worry
+ * about clashes between our early calls to ioremap() that start growing down
+ * from ioremap_base being run into the VM area allocations (growing upwards
+ * from VMALLOC_START). For this reason we have ioremap_bot to check when
+ * we actually run into our mappings setup in the early boot with the VM
+ * system. This really does become a problem for machines with good amounts
+ * of RAM. -- Cort
+ */
+#define VMALLOC_OFFSET (0x1000000) /* 16M */
+
+#define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
+
+#ifdef CONFIG_KASAN_VMALLOC
+#define VMALLOC_END ALIGN_DOWN(ioremap_bot, PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
+#else
+#define VMALLOC_END ioremap_bot
+#endif
+
+#define MODULES_END ALIGN_DOWN(PAGE_OFFSET, SZ_256M)
+#define MODULES_VADDR (MODULES_END - SZ_256M)
+
+#ifndef __ASSEMBLY__
+#include <linux/sched.h>
+#include <linux/threads.h>
+
+/* Bits to mask out from a PGD to get to the PUD page */
+#define PGD_MASKED_BITS 0
+
+#define pte_ERROR(e) \
+ pr_err("%s:%d: bad pte %llx.\n", __FILE__, __LINE__, \
+ (unsigned long long)pte_val(e))
+#define pgd_ERROR(e) \
+ pr_err("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
+/*
+ * Bits in a linux-style PTE. These match the bits in the
+ * (hardware-defined) PowerPC PTE as closely as possible.
+ */
+
+#define pte_clear(mm, addr, ptep) \
+ do { pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, 0, 0); } while (0)
+
+#define pmd_none(pmd) (!pmd_val(pmd))
+#define pmd_bad(pmd) (pmd_val(pmd) & _PMD_BAD)
+#define pmd_present(pmd) (pmd_val(pmd) & _PMD_PRESENT_MASK)
+static inline void pmd_clear(pmd_t *pmdp)
+{
+ *pmdp = __pmd(0);
+}
+
+
+/*
+ * When flushing the tlb entry for a page, we also need to flush the hash
+ * table entry. flush_hash_pages is assembler (for speed) in hashtable.S.
+ */
+extern int flush_hash_pages(unsigned context, unsigned long va,
+ unsigned long pmdval, int count);
+
+/* Add an HPTE to the hash table */
+extern void add_hash_page(unsigned context, unsigned long va,
+ unsigned long pmdval);
+
+/* Flush an entry from the TLB/hash table */
+static inline void flush_hash_entry(struct mm_struct *mm, pte_t *ptep, unsigned long addr)
+{
+ if (mmu_has_feature(MMU_FTR_HPTE_TABLE)) {
+ unsigned long ptephys = __pa(ptep) & PAGE_MASK;
+
+ flush_hash_pages(mm->context.id, addr, ptephys, 1);
+ }
+}
+
+/*
+ * PTE updates. This function is called whenever an existing
+ * valid PTE is updated. This does -not- include set_pte_at()
+ * which nowadays only sets a new PTE.
+ *
+ * Depending on the type of MMU, we may need to use atomic updates
+ * and the PTE may be either 32 or 64 bit wide. In the later case,
+ * when using atomic updates, only the low part of the PTE is
+ * accessed atomically.
+ */
+static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, pte_t *p,
+ unsigned long clr, unsigned long set, int huge)
+{
+ pte_basic_t old;
+
+ if (mmu_has_feature(MMU_FTR_HPTE_TABLE)) {
+ unsigned long tmp;
+
+ asm volatile(
+#ifndef CONFIG_PTE_64BIT
+ "1: lwarx %0, 0, %3\n"
+ " andc %1, %0, %4\n"
+#else
+ "1: lwarx %L0, 0, %3\n"
+ " lwz %0, -4(%3)\n"
+ " andc %1, %L0, %4\n"
+#endif
+ " or %1, %1, %5\n"
+ " stwcx. %1, 0, %3\n"
+ " bne- 1b"
+ : "=&r" (old), "=&r" (tmp), "=m" (*p)
+#ifndef CONFIG_PTE_64BIT
+ : "r" (p),
+#else
+ : "b" ((unsigned long)(p) + 4),
+#endif
+ "r" (clr), "r" (set), "m" (*p)
+ : "cc" );
+ } else {
+ old = pte_val(*p);
+
+ *p = __pte((old & ~(pte_basic_t)clr) | set);
+ }
+
+ return old;
+}
+
+/*
+ * 2.6 calls this without flushing the TLB entry; this is wrong
+ * for our hash-based implementation, we fix that up here.
+ */
+#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
+static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
+ unsigned long addr, pte_t *ptep)
+{
+ unsigned long old;
+ old = pte_update(mm, addr, ptep, _PAGE_ACCESSED, 0, 0);
+ if (old & _PAGE_HASHPTE)
+ flush_hash_entry(mm, ptep, addr);
+
+ return (old & _PAGE_ACCESSED) != 0;
+}
+#define ptep_test_and_clear_young(__vma, __addr, __ptep) \
+ __ptep_test_and_clear_young((__vma)->vm_mm, __addr, __ptep)
+
+#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
+static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep)
+{
+ return __pte(pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, 0, 0));
+}
+
+#define __HAVE_ARCH_PTEP_SET_WRPROTECT
+static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep)
+{
+ pte_update(mm, addr, ptep, _PAGE_RW, 0, 0);
+}
+
+static inline void __ptep_set_access_flags(struct vm_area_struct *vma,
+ pte_t *ptep, pte_t entry,
+ unsigned long address,
+ int psize)
+{
+ unsigned long set = pte_val(entry) &
+ (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
+
+ pte_update(vma->vm_mm, address, ptep, 0, set, 0);
+
+ flush_tlb_page(vma, address);
+}
+
+#define __HAVE_ARCH_PTE_SAME
+#define pte_same(A,B) (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HASHPTE) == 0)
+
+#define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT)
+#define pmd_page(pmd) pfn_to_page(pmd_pfn(pmd))
+
+/*
+ * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
+ * are !pte_none() && !pte_present().
+ *
+ * Format of swap PTEs (32bit PTEs):
+ *
+ * 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * <----------------- offset --------------------> < type -> E H P
+ *
+ * E is the exclusive marker that is not stored in swap entries.
+ * _PAGE_PRESENT (P) and __PAGE_HASHPTE (H) must be 0.
+ *
+ * For 64bit PTEs, the offset is extended by 32bit.
+ */
+#define __swp_type(entry) ((entry).val & 0x1f)
+#define __swp_offset(entry) ((entry).val >> 5)
+#define __swp_entry(type, offset) ((swp_entry_t) { ((type) & 0x1f) | ((offset) << 5) })
+#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> 3 })
+#define __swp_entry_to_pte(x) ((pte_t) { (x).val << 3 })
+
+static inline int pte_swp_exclusive(pte_t pte)
+{
+ return pte_val(pte) & _PAGE_SWP_EXCLUSIVE;
+}
+
+static inline pte_t pte_swp_mkexclusive(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_SWP_EXCLUSIVE);
+}
+
+static inline pte_t pte_swp_clear_exclusive(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~_PAGE_SWP_EXCLUSIVE);
+}
+
+/* Generic accessors to PTE bits */
+static inline int pte_write(pte_t pte) { return !!(pte_val(pte) & _PAGE_RW);}
+static inline int pte_read(pte_t pte) { return 1; }
+static inline int pte_dirty(pte_t pte) { return !!(pte_val(pte) & _PAGE_DIRTY); }
+static inline int pte_young(pte_t pte) { return !!(pte_val(pte) & _PAGE_ACCESSED); }
+static inline int pte_special(pte_t pte) { return !!(pte_val(pte) & _PAGE_SPECIAL); }
+static inline int pte_none(pte_t pte) { return (pte_val(pte) & ~_PTE_NONE_MASK) == 0; }
+static inline bool pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_EXEC; }
+
+static inline int pte_present(pte_t pte)
+{
+ return pte_val(pte) & _PAGE_PRESENT;
+}
+
+static inline bool pte_hw_valid(pte_t pte)
+{
+ return pte_val(pte) & _PAGE_PRESENT;
+}
+
+static inline bool pte_hashpte(pte_t pte)
+{
+ return !!(pte_val(pte) & _PAGE_HASHPTE);
+}
+
+static inline bool pte_ci(pte_t pte)
+{
+ return !!(pte_val(pte) & _PAGE_NO_CACHE);
+}
+
+/*
+ * We only find page table entry in the last level
+ * Hence no need for other accessors
+ */
+#define pte_access_permitted pte_access_permitted
+static inline bool pte_access_permitted(pte_t pte, bool write)
+{
+ /*
+ * A read-only access is controlled by _PAGE_USER bit.
+ * We have _PAGE_READ set for WRITE and EXECUTE
+ */
+ if (!pte_present(pte) || !pte_user(pte) || !pte_read(pte))
+ return false;
+
+ if (write && !pte_write(pte))
+ return false;
+
+ return true;
+}
+
+/* Conversion functions: convert a page and protection to a page entry,
+ * and a page entry and page directory to the page they refer to.
+ *
+ * Even if PTEs can be unsigned long long, a PFN is always an unsigned
+ * long for now.
+ */
+static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
+{
+ return __pte(((pte_basic_t)(pfn) << PTE_RPN_SHIFT) |
+ pgprot_val(pgprot));
+}
+
+/* Generic modifiers for PTE bits */
+static inline pte_t pte_wrprotect(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~_PAGE_RW);
+}
+
+static inline pte_t pte_exprotect(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~_PAGE_EXEC);
+}
+
+static inline pte_t pte_mkclean(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~_PAGE_DIRTY);
+}
+
+static inline pte_t pte_mkold(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~_PAGE_ACCESSED);
+}
+
+static inline pte_t pte_mkexec(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_EXEC);
+}
+
+static inline pte_t pte_mkpte(pte_t pte)
+{
+ return pte;
+}
+
+static inline pte_t pte_mkwrite_novma(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_RW);
+}
+
+static inline pte_t pte_mkdirty(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_DIRTY);
+}
+
+static inline pte_t pte_mkyoung(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_ACCESSED);
+}
+
+static inline pte_t pte_mkspecial(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_SPECIAL);
+}
+
+static inline pte_t pte_mkhuge(pte_t pte)
+{
+ return pte;
+}
+
+static inline pte_t pte_mkprivileged(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~_PAGE_USER);
+}
+
+static inline pte_t pte_mkuser(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_USER);
+}
+
+static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
+{
+ return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot));
+}
+
+
+
+/* This low level function performs the actual PTE insertion
+ * Setting the PTE depends on the MMU type and other factors.
+ *
+ * First case is 32-bit in UP mode with 32-bit PTEs, we need to preserve
+ * the _PAGE_HASHPTE bit since we may not have invalidated the previous
+ * translation in the hash yet (done in a subsequent flush_tlb_xxx())
+ * and see we need to keep track that this PTE needs invalidating.
+ *
+ * Second case is 32-bit with 64-bit PTE. In this case, we
+ * can just store as long as we do the two halves in the right order
+ * with a barrier in between. This is possible because we take care,
+ * in the hash code, to pre-invalidate if the PTE was already hashed,
+ * which synchronizes us with any concurrent invalidation.
+ * In the percpu case, we fallback to the simple update preserving
+ * the hash bits (ie, same as the non-SMP case).
+ *
+ * Third case is 32-bit in SMP mode with 32-bit PTEs. We use the
+ * helper pte_update() which does an atomic update. We need to do that
+ * because a concurrent invalidation can clear _PAGE_HASHPTE. If it's a
+ * per-CPU PTE such as a kmap_atomic, we also do a simple update preserving
+ * the hash bits instead.
+ */
+static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte, int percpu)
+{
+ if ((!IS_ENABLED(CONFIG_SMP) && !IS_ENABLED(CONFIG_PTE_64BIT)) || percpu) {
+ *ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE) |
+ (pte_val(pte) & ~_PAGE_HASHPTE));
+ } else if (IS_ENABLED(CONFIG_PTE_64BIT)) {
+ if (pte_val(*ptep) & _PAGE_HASHPTE)
+ flush_hash_entry(mm, ptep, addr);
+
+ asm volatile("stw%X0 %2,%0; eieio; stw%X1 %L2,%1" :
+ "=m" (*ptep), "=m" (*((unsigned char *)ptep+4)) :
+ "r" (pte) : "memory");
+ } else {
+ pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, pte_val(pte), 0);
+ }
+}
+
+/*
+ * Macro to mark a page protection value as "uncacheable".
+ */
+
+#define _PAGE_CACHE_CTL (_PAGE_COHERENT | _PAGE_GUARDED | _PAGE_NO_CACHE | \
+ _PAGE_WRITETHRU)
+
+#define pgprot_noncached pgprot_noncached
+static inline pgprot_t pgprot_noncached(pgprot_t prot)
+{
+ return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) |
+ _PAGE_NO_CACHE | _PAGE_GUARDED);
+}
+
+#define pgprot_noncached_wc pgprot_noncached_wc
+static inline pgprot_t pgprot_noncached_wc(pgprot_t prot)
+{
+ return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) |
+ _PAGE_NO_CACHE);
+}
+
+#define pgprot_cached pgprot_cached
+static inline pgprot_t pgprot_cached(pgprot_t prot)
+{
+ return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) |
+ _PAGE_COHERENT);
+}
+
+#define pgprot_cached_wthru pgprot_cached_wthru
+static inline pgprot_t pgprot_cached_wthru(pgprot_t prot)
+{
+ return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) |
+ _PAGE_COHERENT | _PAGE_WRITETHRU);
+}
+
+#define pgprot_cached_noncoherent pgprot_cached_noncoherent
+static inline pgprot_t pgprot_cached_noncoherent(pgprot_t prot)
+{
+ return __pgprot(pgprot_val(prot) & ~_PAGE_CACHE_CTL);
+}
+
+#define pgprot_writecombine pgprot_writecombine
+static inline pgprot_t pgprot_writecombine(pgprot_t prot)
+{
+ return pgprot_noncached_wc(prot);
+}
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* _ASM_POWERPC_BOOK3S_32_PGTABLE_H */